An rare muscle condition called rhabdomyolysis has damaged the off-season habits of American Melanie Oudin, and the 22-year-old American is unsure of when she will be back on the court.

Late last week in an interview with the Associated Press, Oudin said that she has no strength in her arms and that her muscles are "completely ruptured" in her arms. The condition caused her arms to "swell like balloons" and has her doctor refusing her the right to swing a racquet or lift weights. Her conditioning has been reduced to an hour of running each day.

According to the National Institute of Health, rhabdomyolysis is the breakdown of muscle fibers that leads to the release of muscle fiber contents (myoglobin) into the blood stream. It is harmful to the kidney and often causes kidney damage. Oudin said during a typical offseason, she would be on the court and doing fitness at least six hours per day.

As a result, she has already withdrawn from the Auckland tournament, which begins Dec. 30, and is now questionable for the Australian Open.

The National Institute of Health's prognosis is that people with milder cases may return to normal activities within a few weeks to a month, but will still have problems with fatigue and muscle pain, suggesting Oudin could be out quite a bit longer.

Oudin went 30-24 in 2013 and is ranked No. 127 in the world. She has been ranked as high as 40th in the world and has won one career singles title to date.